Wire-forming apparatus and method

ABSTRACT

This disclosure concerns forming wire into a serpentine pattern by means of two driven belts, each having a plurality of spaced apart projections for temporarily retaining the wire, which wire is engaged by the projections on one moving belt then the other in an alternating manner and then directing the belts away from each other after the wire is engaged thereby forming the serpentine pattern.

United States Patent Inventors Appl. No.

Filed Patented Assignee John Clifton Rentz Salfords, England;

William B. Williams, King of Prussia, Pa. 763,725

Sept. 30, 1968 Feb. 9, 1971 General Electric Company a corporation of New York WIRE-FORMING APPARATUS AND METHOD 7 Claims, 5 Drawing Figs.

US. Cl 140/71, [40/105, 72/190 Int. Cl 1321f l/04 Field of Search 140/71 lO5,112;72/190.191,SB

References Cited UNITED STATES PATENTS Southwell et al7 White Mackendrick Huck Daly Crise Primary Examiner-Lowell A. Larson Att0rneysLawrence R. Kempton, Frederick P. Weidner, J L,

Frank L. Neuhauser and Oscar B Waddell ABSTRACT: This disclosure concerns forming wire into a serpentine pattern by means of two dlriven belts, each having a plurality of spaced apart projections for temporarily retaining the wire, which wire is engaged by the projections on one moving belt then the other in an alternating manner and then directing the belts away from each other after the wire is engaged thereby forming the serpentine pattern.

PATENTED FEB 9l97| sum 3 or 3 Fig. 2.

Inventors: John C.v E entz, William B. WHHams b Q Q Attorne l I IIIIIII "III WIRE-FORMING APPARATUSAND METHOD BACKGROUND OF THE INVENTION The present invention relates to methods and apparatus for forming wire into a serpentine pattern.

.An electrically heated bedcover is an example of an appliance utilizing a resistance heater wire which extends back and forth through parallel channels formed between opposite plies of the bedcover in what may be referred to as a serpentine pattern. While the wire may be manually inserted through the channels, the modern trend toward automation and mass production indicates a desirability for providing an apparatus which automatically forms a wire into a serpentine pattern efficiently in a continuous manner so that the formed wire may thereafter be deposited on and sandwiched between two fabrics moving at the same rate of speed as the formed wire. While the present invention lends itself very well to forming a wire for use in an electrically heated bedcover, it is to be understood that the same method and apparatus may be used in forming wire into a serpentine pattern for other end uses.

SUMMARY OF THE INVENTION In accordance with this invention first and second endless belts are provided which are driven at the same rate of speed and each of which carries a plurality of spaced wire-engaging projections. Means for supporting and positioning the belts in predetermined relationship to each other is provided in the form of sprockets which serve to guide the belts along a predetermined path of travel. The projections on one belt engage a wire to be formed alternately with the projections on the other belt; and, after being so engaged; the projections with the wire on one belt are moved apart from the projections with the wire on the other belt to cause the wire to be fonned into a serpentine pattern. The formed wire may thereafter be removed from the projections.

It is an object of the present invention to provide an improved method and apparatus for continuously forming wire into a serpentine pattern at a relatively rapid commercially practical rate of speed without subjecting the wire to undue strain.

A further object is to provide means to assure that a pair of endless belts, used as a part of the apparatus to form wire in a serpentine pattern, are driven at the same rate of speed.

A still further object is to provide an apparatus and method which forms a wire into a serpentine pattern and deposits the formed wire on a fabric layer moving at the same speed as the formed wire.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view, in diagrammatic form, illustrating the wire-forming apparatus and particularly the portion of the apparatus where the wire to be formed is introduced to the projections on the belts.

FIG. la is a continuation of FIG. 1 illustrating the portion of the wire-forming apparatus where the wire in serpentine form is removed from the projections.

FIG. 2 is a view taken along line 2'2 of FIG. 1.

FIG. 3 is a front elevation of the apparatus illustrated at FIG. 2.

FIG. 4 is a continuation of FIG; 1a illustrating means for depositing the formed wire on a moving fabric.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 and 1a, a first endless belt of the link chain type is supported from and positioned by a plurality of sprockets 11-18. It is to be understood that the sprockets are to be supported on any suitable framework which framework may rest on the floor. Each of the sprockets, with the exception of sprockets 17 and 18, are rotatably mounted such as through the medium of sleeve bearings on fixed support rods 19, and the support rods are secured to appropriate framework (not shown) in the apparatus. The sprockets 17 and 18 are fixedly secured to respective drive shafts 20 and 21. In other words the sprockets l7 and 18 are used to drive the belt 10 and the other sprockets are used only for supporting and guiding the belt. A plurality of wire-engaging projections 22 in the form of pulleys are secured to the belt 10 so as to extend vertically downwardly therefrom. Each pulley is rotatably mounted on a rod 23, and the rods are secured to the belt. While for purposes of clarity we have illustrated only a limited number of pulleys, it is to be understood that these pulleys are equidistantly spaced from each other along the entire length of the belt.

A second endless belt 24, also of the link chain type. is driven by sprockets 25 and 26 fixedly secured to respective drive shafts 21 and 20. Other sprockets 2732 are rotatably mounted on fixed support rods 33, and these latter sprockets serve to position and guide the belt 24 along a predetermined path of travel. The second belt also carries a plurality of wire engaging pulleys 34 spaced equidistantly from each other along the entire length of the belt. The pulleys 34 project vertically upwardly from the belt 24.

As reviewed at FIG. 1, the belt 10 includes a first span 35, and the second belt 24 also includes a first span 36. The spans 35 and 36 extend toward each other in the direction of movement of the belts until they intersect an imaginary vertical line through both belts at a first crossover point of the belts. From the crossover point, the belt 10.has a second span 37 which is directed away from a second span 38 of the belt 24 in the direction of movement of the belts.

A flexible wire 39 which is to be formed into a serpentine pattern is fed through a guide tube 40 from an appropriate supply roll to the first crossover point of the belts. This wire is engaged alternately by the pulleys on the two belts as will be set forth later in more detail when the operation of the apparatus is described. As seen clearly at FIG. 2, the pulleys on each of the belts are in the same horizontal plane at the first crossover point of the belts.

In order to supply movement to the belts, the first drive shaft 20 is rotated in the direction of the arrow by a suitable motor. As stated above, first and second sprockets 17 and 26 are fixedly secured to the shaft 20, and these sprockets are in driving engagement respectively with,the first and second belts l0 and 24. A gear 41 is also fixedly secured to the shaft 20. Another gear 42 is fixedly secured to the second drive shaft 21, and the gear 42 is identical to the gear 41. The two gears mesh with each other so that the first shaft 20, through the medium of the gears 41 and 42 drives the second shaft 21 at the'same speed asthe first drive shaft 20 is driven. The sprockets 18 and 25 are secured to the shaft 21, and these sprockets are in driving engagement respectively with the first and second belts 10 and 24.

From the above it will be appreciated that assurance is gained that the belts 10 and 24 move at the same rate of speed first due to the fact that the gears 41 and 42 are identical; and secondly, by virtue of the fact that there are sprockets on each of the drive shafts which are in driving engagement with each of the endless belts. Because the belts move at the same rate of speed there is no danger of the pulleys colliding at the first crossover point, assuming that the belts have been properly positioned initially so that the pulleys 22 on one belt alternate with the pulleys 34 on the other belt in passing through the crossover point. This danger of collision is also obviated by having the driving sprockets 17 and 26 on the shaft 20 spaced relatively close to the driving sprockets l8 and 25 on the shaft 21 so that there will only be a minimal, if any, chain sag between the sprockets l7 and 18 and between the sprockets 25 and 26.

A second crossover point for the belts occurs in the vicinity of the sprockets 15 and 31 havinga common supporting rod 43. There can be no collision of the pulleys at this second crossover point because the distance between sprockets l5 and 31 is greater than the total distances the'pulleys project from the belts. In other words, the pulleys 22 on belt 10 are in a horizontal plane above the horizontal plane of the pulleys 34 at this second crossover point.

The manner in which the formed wire is removed from the belts l and 24 may be clearly understood by now referring to FiGS. la and 3. The second span 37 (FIG. I) of belt continues around sprocket lll to sprocket 12. Between these latter sprockets, the belt 10 is directed inwardly toward the other belt 24 and vertically upwardly. Because the formed wire is now clamped between opposed rubber belts A and 45 and between rubber belts 46 and 47 moving in the direction of the arrows, the pulleys 22 remove themselves from the bight portions of the formed wire and continue empty around the remaining sprockets until they again engage the wire 39 at the crossover point between the first and second spans 35 and 37 shown in FIG. 1. The endless belt 24 is directed inwardly and vertically downwardly between the sprockets 27 and 28 so that the pulleys 34 are removed from the bight portions at the opposite side of the formed wire. The belts 44-47 all are moved at the same rate of speed as the endless belts K0 and 24 such as by a separate motor or by linking the drive means for the belt 10 and 24 to the drive means for the belts 44-47 with a suitable chain and sprocket arrangement.

Before the wire 39, which has been formed into a desired serpentine pattern, emerges from the rubber belts 44-47 (FIG. 4) the bight portions at opposite ends of the wire are picked up by arms 48 carried by endless conveyor 50 and arms 49 carried by endless conveyor 51 along opposite sides of the formed wire. The arms are spaced equidistantly from each other along the entire length of the conveyors and may be formed of spring steel. The conveyors S0 and 51 may be of the chain link type driven by appropriate drive sprockets 52. These conveyors 50 and 51 are also driven at the same speed and in the same direction of travel as endless belts l0 and 24 which are conveying the formed wire in serpentine pattern.

After the formed wire is removed from the arms 48 and 49, the wire may be deposited on a fabric layer 53 moving in the direction of the arrow (FIG. 4) at the same speed as the conveyors 50 and 51. It is to be understood that a second fabric layer (not shown) may then be placed on top of the formed wire, and the two fabric layers may be secured together in any suitable manner such as by applying an adhesive along spaced parallel lines extending between adjacent runs of the wire.

From the above, it should be clear that the apparatus operates in the following manner to form wire into a serpentine pattern: With the apparatus at rest, an operator manually feeds wire 39 through the feed tube 40 and between the two endless belts 10 and 24 at the first crossover point. The wire is then manually threaded around the opposite pulleys 22 and 34 in a serpentine pattern until the end of the wire is disposed and gripped between the opposed surface of the rubber belts 44- --47. The drive shaft is then started in motion to move the belts l0 and 24 at a predetermined rate of speed and, at the same time, the belts Ed-4'7 are put into motion at this same rate of speed. As the wire emerges from the guide tube it is engaged first by a pulley 3 1 on belt 24, then by a pulley 22 on belt 10. This alternate engagement of the pulleys coupled with the fact the second spans 37 and 38 are now moving apart from each other causes the wire to be formed in a serpentine pattern, and the formed wire is continually advanced to the formed wire removal means including the rubber belts 44-47 and the arms 48 and 49 carried by the conveyors 50 and 51. As stated, the formed wire is continually deposited on a fabric layer 53 moving at the same speed as the belts to provide a continuous operation.

The strain to which the wire is subjected is dependent in part on the speed of the moving endless belts. We have operated the apparatus of the present invention to advance the formed wire at speeds quite suitable for mass producing electrically heated bedcovers without incurring any breakage of the flexible wire of a size commonly used in electrically heated bedcovers.

The foregoing is a description of the preferred embodiment of the invention, and variations may be made to the apparatus and method without departing from the spirit of the invention, as defined in the appended claims.

We claim:

1. A wire-forming apparatus for forming wire into a serpentine pattern, said apparatus comprising:

a. first and second endless belts crossing each other in spacing relationship;

b. means for driving said belts at essentially the same rate of speed each along a predetermined path of travel;

c. a plurality of spaced wire-engaging projections connected to each of said belts;

d. means for feeding the wire to said wire-engaging projections at the crossing of said belts;

e. means supporting and positioning said belts in predetermined relationship to each other for said wire-engaging projections of said first belt to engage the wire alternately with the wire engaging projections of said second belt; and

. said belt-supporting means including elements for directing said belts away from each other after the wire has been engaged alternately by said wire-engaging means whereby said wire is formed into a serpentine pattern.

2. Apparatus as set forth in claim 1 wherein each of said belts includes a first span, said first spans being directed toward each other in the direction of movement of said belts until said belts intersect an imaginary vertical line through said belts; a second span on each of said belts, said second spans being directed away from each other in the direction of movement of said second spans from the imaginary vertical line of intersection; said projections on said first belt extend 'vertically upwardly from said first belt, and said projections on said second belt extend vertically downwardly from said second belt; whereby said wire is contacted by the projections on each of said belts while said belts are traversing the second spans.

3. The apparatus as set forth in claim 1 wherein said driving means includes first and second drive shafts, and each of said drive shafts have first and second belt-engaging means secured thereto; said first belt-engaging means on each of said shafts drivingly engaging said first endless belt, and said second belt engaging means on each of said shafts drivingly engaging said second belt.

4. The apparatus as set forth in claim 1 wherein said wireengaging projections on each belt are spaced equidistantly from each other.

5. The apparatus as set forth in claim 2 wherein the end of said second spans remote from said first spans are directed inwardly toward each other and vertically away from each other for removing said wire from said projections; and said apparatus further includes means for advancing said formed wire after said wire has been removed from said projections to deposit said formed wire on a continuously moving fabric.

6. A method forming wire into a serpentine pattern includa. moving first and second endless belts at substantially the same rate of speed each along a predetermined path of travel that provides for the belts to cross each other in spaced relationship;

b. feeding the wire to said belts at the crossing;

c. engaging said wire alternately by wire engaging projections carried by said first and second belts;

(1. moving the engaging means on the belts apart from each other after the wire has been engaged by the engaging means on each belt to form the wire into a serpentine pattern; and

e. removing the formed wire from the projections.

7. The method of claim 6 which includes the additional step of disposing the serpentine formed wire on a fabric ply. 

1. A wire-forming apparatus for forming wire into a serpentine pattern, said apparatus comprising: a. first and second endless belts crossing each other in spacing relationship; b. means for driving said belts at essentially the same rate of speed each along a predetermined path of travel; c. a plurality of spaced wire-engaging projections connected to each of said belts; d. means for feeding the wire to said wire-engaging projections at the crossing of said belts; e. means supporting and positioning said belts in predetermined relationship to each other for said wire-engaging projections of said first belt to engage the wire alternately with the wire engaging projections of said second belt; and f. said belt-supporting means including elements for directing said belts away from each other after the wire has been engaged alternately by said wire-engaging means whereby said wire is formed into a serpentine pattern.
 2. Apparatus as set forth in claim 1 wherein each of said belts includes a first span, said first spans being directed toward each other in the direction of movement of said belts until said belts intersect an imaginary vertical line through said belts; a second span on each of said belts, said second spans being directed away from each other in the direction of movement of said second spans from the imaginary vertical line of intersection; said projections on said first belt extend vertically upwardly from said first belt, and said projections on said second belt extend vertically downwardly from said second belt; whereby said wire is contacted by the projections on each of said belts while said belts are traversing the second spans.
 3. The apparatus as set forth in claim 1 wherein said driving means includes first and second drive shafts, and each of said drive shafts have first and second belt-engaging means secured thereto; said first belt-engaging means on each of said shafts drivingly engaging said first endless belt, and said second belt engaging means on each of said shafts drivingly engaging said second belt.
 4. The apparatus as set forth in claim 1 wherein said wire-engaging projections on each belt are spaced equidistantly from each other.
 5. The apparatus as set forth in claim 2 wherein the end of said second spans remote from said first spans are directed inwardly toward each other and vertically away from each other for removing said wire from said projections; and said aPparatus further includes means for advancing said formed wire after said wire has been removed from said projections to deposit said formed wire on a continuously moving fabric.
 6. A method forming wire into a serpentine pattern including: a. moving first and second endless belts at substantially the same rate of speed each along a predetermined path of travel that provides for the belts to cross each other in spaced relationship; b. feeding the wire to said belts at the crossing; c. engaging said wire alternately by wire engaging projections carried by said first and second belts; d. moving the engaging means on the belts apart from each other after the wire has been engaged by the engaging means on each belt to form the wire into a serpentine pattern; and e. removing the formed wire from the projections.
 7. The method of claim 6 which includes the additional step of disposing the serpentine formed wire on a fabric ply. 